Added dropdown selection for results per page. Changed the rating filters from "1+", "2+", etc. to stars, like how ratings of items are displayed. Added a default image to the results/product view, if imgUrl is empty. Also made the images on the results pages links to the product pages.

*added another select tag into results view, for selecting results per page
*added positioning class to retrevo.css, to separate the per page dropdown from order by
*added a new partial, to generate the stars for the rating filter
*added <a> tags around the thumbnails in the results view
*added some javascript in the results view, to make sure that when changing results per page, the start parameter remains a multiple of results per page
*earned my "full stack engineer" title